Teachable Moments | November 18, 2020
Earth Satellite Joins NASA Fleet to Monitor Sea Level, Improve Weather Forecasts
Learn about the mission and find out how to make classroom connections to NASA Earth science – plus explore related teaching and learning resources.
In the News
A new spacecraft that will collect vital sea-surface measurements for better understanding climate change and improving weather predictions is joining the fleet of Earth science satellites monitoring our changing planet from space. A U.S.-European partnership, the Sentinel-6 Michael Freilich satellite continues a long tradition of collecting scientific data from Earth orbit. It’s named in honor of NASA’s former Earth Science Division director and a leading advocate for ocean measurements from space.
Read on to find out how the mission will measure sea-surface height for the next 10 years and provide atmospheric data to help better predict weather. Plus, find out how to watch the launch online and explore related teaching resources to bring NASA Earth science into the classroom and incorporate sea level data into your instruction.
How It Works
The Sentinel-6 Michael Freilich satellite is designed to measure sea-surface height and improve weather predictions. Once in orbit, it will be able to measure sea-surface height – with accuracy down to the centimeter – over 90% of the world’s oceans every 10 days. It will do this using a suite of onboard science tools, or instruments.
To measure sea-surface height, a radar altimeter will send a pulse of microwave energy to the ocean’s surface and record how long it takes for the energy to return. The time it takes for the signal to return varies depending on the height of the ocean – a higher ocean surface results in a shorter return time, while a lower ocean surface results in a longer return time. A microwave radiometer will measure delays that take place as the signal travels through the atmosphere to correct for this effect and provide an even more precise measurement of sea-surface height.
To measure atmospheric data, Sentinel-6 Michael Freilich is equipped with the Global Navigation Satellite System - Radio Occultation, or GNSS-RO, instrument, which will measure signals from GPS satellites – the same ones you use to navigate on Earth. As these satellites move below or rise above the horizon from Sentinel-6 Michael Freilich's perspective, their signals slow down, change frequency and bend as a result of the phenomenon known as refraction. Scientists can use these changes in the GPS signal to measure small shifts in temperature, moisture content, and density in the atmosphere. These measurements can help meteorologists improve weather forecasts.
Why It's Important
Scientists from around the world have been collecting sea level measurements for more than a century. The data – gathered from tide gauges, sediment cores, and space satellites – paint a clear picture: sea level is rising. Looking at the average height of the sea across the planet, we see that in the last 25 years global sea level has been rising an average of 0.13 inches (3.3 mm) per year. This average is increasing each year (in the 2000s, it was 0.12 inches, or 3.0 mm, per year) as is the rate at which it’s increasing. That means that sea level is rising, and it’s rising faster and faster. Since 1880, global sea level has risen more than eight inches (20 cm). By 2100, it is projected to rise another one to four feet (30 to 122 cm).
Measuring sea level from space provides scientists with global measurements of Earth’s oceans in a matter of days, including areas far from shore where measurements aren’t practical or possible. Starting in 1992 with the launch of the TOPEX/Poseidon mission, the record of sea level measurements from space has continued uninterrupted, providing an increasingly detailed picture of Earth’s rising seas. The Sentinel-6 Michael Freilich satellite – and its twin, which will launch in 2025 – will extend those measurements to 2030, allowing scientists to continue collecting vital information about Earth’s changing oceans and climate.
Unlike previous satellites that measured sea level, Sentinel-6 Michael Freilich has the capability to measure sea level variations more accurately near coastlines, giving scientists insight into changes that can have direct impacts on communities and livelihoods, such as commercial fishing and ship navigation.
With rising seas already impacting people and communities, it's important to understand not just how much seas are rising, but also where and how quickly they are rising. Data from instruments on Sentinel-6 Michael Freilich can be combined with data from other satellites to get a clearer picture of what's contributing to sea level rise and where. For example, by looking at the satellite's radar altimeter measurements along with gravity measurements from the GRACE-FO mission, scientists can better determine how melting ice and thermal expansion are contributing to sea level rise. And by tracking the movement of warm water (which stands taller than cold water), scientists can better predict the rapid expansion of hurricanes.
Watch the Launch
Scheduled to launch at 9:17 a.m. PST (12:17 p.m. EST) on November 21, Sentinel-6 Michael Freilich will launch atop a SpaceX Falcon 9 rocket from Vandenberg Air Force Base in California.
Watch a live broadcast of the launch from the Vandenberg Air Force Base on NASA TV and the agency’s website. Visit the Sentinel-6 Michael Freilich website to explore more news about the mission. Follow launch updates on NASA's Twitter, Facebook and Instagram accounts.
Make classroom connections to NASA Earth science with lessons about rising seas, thermal expansion and ice melt, data collection and graphing, and engineering. Plus explore independent activities and experiments students can do at home, video playlists, and more:
Lesson Collection for Educators
Explore these standards-aligned STEM lessons about launches, Earth satellites, and sea level rise to make classroom connections to the Sentinel-6 Michael Freilich mission.
Learn With NASA – YouTube Playlist
This YouTube playlist for students and teachers features explainers about the causes and effects of sea level rise and how NASA is studying our changing planet – plus related STEM activities and experiments for students.
Teaching Space With NASA
Watch education webinars featuring NASA experts and education specialists talking about Earth science and more, explore related resources, and register to participate in an upcoming live Q&A.
Teachable Moments: The Science of Earth's Rising Seas
How do we know sea-level rise is happening and what’s causing it? Learn about the NASA satellites studying the problem and get students exploring the data through math.
Teachable Moments: NASA's Eyes on Extreme Weather
Learn about the causes and effects of extreme weather including hurricanes, floods, droughts and wildfires, plus how NASA studies them.
Activities for Students
Get students engaged in science and engineering related to the Sentinel-6 Michael Freilich mission with these videos and independent activities.
Learning Space With NASA at Home
Explore Earth and space science activities students can do with NASA at home, watch live stream events and video tutorials, plus explore tips for home-based learning!
- Press Kit: Sentinel-6 Michael Freilich
- Website: Sentinel-6 Michael Freilich
- Article: Meet the People Behind the Sentinel-6 Michael Freilich Spacecraft
- Article: 5 Things to Know About Sentinel-6 Michael Freilich
- Website: NASA Climate Change
- Website: Sea Level Science
- Website: NASA Climate Kids
- Article for Kids: How Do We Measure Sea Level?
- Interactive: Explore Earth Now
- Facts & Figures: Climate Change - Evidence
- Gallery: Images of Change
- Podcast: On a Mission
- Multimedia: NASA climate images, videos, and graphics
- Social Media: List of NASA social media channels
- Events: NASA Live
Recursos en Español
TAGS: Teachable Moments, Educators, Teachers, Parents, K-12 Education, Launch, Mission, Earth, Satellite, Earth Science, Climate Change, Sentinel-6 Michael Freilich, Sea Level, Sea Level Rise, Climate TM